Recently, it has been demanded to develop an art for forming a metallic conductive film on an insulator film such as a flexible circuit board used in electronics or the like, and an electromagnetic wave shielding film used in plasma displays. Generally, for applying a metallic film thickly, an electrolytic plating process is preferably employed in view of productivity, cost and easiness in controlling thickness. However, since a direct electrolytic plating on an insulator film having a large surface resistivity cannot be performed, it is currently conducted that a thin metallic film is formed on an insulator film according to a sputtering method, a vacuum deposition method or an electroless plating method, thereafter electrolytic plating is performed thereon to increase the thickness to a desired level.
Under the present situation, it is necessary to perform an electroless plating process until a surface resistivity is 1 Ω/Sq or less in order to perform an electrolytic plating process. For this reason, there are problems in productivity such as a requirement for a long period of time to perform an electroless plating process or a low line speed for sputtering operation.
As shown in Patent Document 1, a light transmitting conductive film produced by utilizing a photosensitive material using a silver salt has excellent advantages such as a high transparency owing to its capability of precisely forming a fine line pattern and a mass production at a low cost compared with those according to other methods. However, since a developed silver mesh has a high resistance in this film, the film requires a combination of an electroless plating process with an electrolytic plating process. In addition, the productivity thereof is poor and plating cost is high. Accordingly, there has been a demand to solve these problems.
Patent Document 1: JP-A-2004-221564